Flame-retardant cellulosic material,composition and method for making same



meal imes it. i 111E116 3,428,480 FLAME-RETARDANT CELLULOSIC MATERIAL, COMPOSITION AND METHOD FOR MAKING SAME George M. Wagner, Lewiston, and Rex A. Schad, North Tonawanda, N.Y., assignors to Hooker Chemical Corporation, Niagara Falls, N.Y., a corporation of New York No Drawing. Filed Feb. 18, 1965, Ser. No. 433,812 US. Cl. 117136 Claims Int. Cl. D06m 15/08, 13/30, 13/08 ABSTRACT OF THE DISCLOSURE This invention relates to an improved flame retardant cellulosic material and more particularly it relates to an improved composition and process for treating cellulosic textile materials to render the flame retardant.

In recent years, numerous compositons have been proposed for use in treating cellulosic materials, such as cellulosic textiles, to render them durably flame retardant. Of these, the most successful have been those wich utilize a tetrakis(hydroxyorgano)phosphonium halide material as the principal flame retarding component of the composition. Although initial flame-retardancy of cellulosic textiles treated with compositions of this type has generally been very good, in some instances, it has been found that after several washings of the treated textile the flame-retardancy may be greatly reduced or even destroyed completely. In order to overcome this difficulty, various modifications of the flame retarding composition have been proposed in order to improve the durability of the flame retardancy to washing of the treated cloth.

One such modification which has been particularly effective is that described in US. Patent 3,054,698, wherein a high softening point polyvinyl chloride resin is admixed with a methylol-phosphorus compound to form the flameretarding composition with which the cellulosic material is treated. Cellulosic textile materials treated with this composition exhibit excellent flame-retarding characteristics both initially and after numerous washings. It has been found, however, although the hand of the textiles treated with this composition is greatly superior to that of fabrics treated with a similar composition only containing a low softening point polyvinyl chloride, in some instances, the hand of these treated textile fabrics is still undesirably firm. Up to the present time, attempts to overcome this problem and produce a fabric having a softer hand, without adversely affecting the durability of the flame-retardant finish, have not been successful.

It is, therefore, an object of the present invention to provide an improved flame-retarding composition for the treatment of cellulosic material and particularly cellulosic textile material.

Patented Feb. 18, 1969 Another object of the present invention is to provide an improved process for the treatment of cellulosic textile materials to render them durably flame retardant.

A further object of the present invention is to provide an improved flame retardant cellulosic textile material, which material is not only durably flame retardant for the life of the fabric but also has a soft hand.

These and other objects will be apparent to those skilled in the art from a description of the invention which follows.

Pursuant to the above objects, the present invention includes a composition, suitable, when dispersed in a solvent, for treating a cellulosic material to render it flame retardant, which composition comprises a tetrakis-(alphahydroxyorgano)phosphonium halide, a water-soluble cyclic nitrogen-containing compound, a water-soluble tertiary amine, a carbamic acid derivative, a halogenated paraffin and a polyvinyl halide composition, it an amount not in excess of 25 by weight of the halogenated paraflim Cellulosic materials, such as cellulosic textiles, when treated with ,the above composition are found to have excellent flame retardant characteristics even after repeated launderings, as well as an excellent, soft hand.

More specifically, in the practice of the present invention, the polymerizable composition with which the cellulosic material is treated is preferably an aqueous composition, i.e., an aqueous solution or an aqueous dispersion, which composition desirably contains the following components in the amount indicated:

Components: Percent by weight Tetrakis( alpha hydroxyorgano) phosphonium halide 6 to 20 Water-soluble cyclic co-polymerizable ni trogen-containing compound 3 to 12 Water-soluble tertiary amine I 1 to 4 Carbamic acid derivative 3 to 12 Halogenated paraffin 2 to 14 Polyvinyl halide composition .02 to 3.5 Water Balance It is to be appreciated, of course, that the above is merely exemplary of the compositions of the present invention and that other proportions of the components I listed, which wi'l impart the desired durable flame retardancy and soft hand to the cellulosic materials treated, may also be employed.

The tetrakis-(alpha hydroxyorgano)phosphonium haliie compound of the subject composition may be further defined as a compound having the formula:

wherein R is selected from the group consisting of hydrogen, lower alkyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkyl radicals having between about 1 and about 6 carbon atoms, lower alkenyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkenyl radicals having between about 1 and about 6 carbon atoms, aryl radicals having between about 5 and about 10 carbon atoms, halogenated aryl radicals having between about 5 and about 10 carbon atoms, cycloalkyl radicals having between about 3 and about 6 carbon atoms, halogenated cycloalkyl radicals having between about 3 and about 6 carbon atoms, and wherein X is a halogen, such as chlorine, bromine,

liuorine or iodine. Typical examples of suitable tetrakis (alpha hydroxyorgano)phosphonium halide compound are tetrakis(hydroxymethyl)phosphonium chloride, tetrakis(hydroxymethyl)phosphonium bromide, tetrakis(hydroxyethyl)phosphonium chloride, tetrakis(alpha hydroxypropyl)phosphonium chloride, tetrakis(alpha hydroxyallyl)phosphonium chloride, tetrakis(alpha-hydroxybenzyl)phosphonium chloride, tetrakis(alpha hydroxymethylcyclohexyl)phosphonium chloride, tetrakis(alphahydroxypropionyl)phosphonium chloride, tetrakis(alphahydroxybutanol)phosphonium chloride, as well as the various halogenated derivatives of these, such as chlorinated and brominated derivatives, such as tetrakis(hydroxychloromethyl)phosphonium chloride, and mixtures thereof. The phosphonium compound may be used in monomer form or in a partially polymerized form, so long as it is still water-soluble. For example, tetrakis(hydroxymethyl)phosphonium chloride, which is the preferred phosphonium compound, may be heated to effect partial polymerization before dissolving it in the impregnating solution.

Water-soluble cyclic nitrogen-containing compounds suitable for use in the present invention include the triazines and the dimethylol cyclic alkylene ureas. Typical examples of suitable triazines include the methylol melamines, such as mono-, di-, and trimethylolmelamine, modified methylol melamines, su h as the triethyl ether of trimethylol melamine; triazones, such as dimethylol triazone; and mixtures thereof. Typical examples of suitable cyclic alkylene ureas include dimethylol ethylene urea, dimethylol propylene urea, and the like. Of these, trimethylol melamine is preferred and for this reason, hereinafter primary reference will be made to this compound.

Carbamic acid derivatives which may be used in formulating the polymerizable impregnating composition of the present invention are exemplified by urea, thiourea, biuret, ethyleneurea, and dicyandiamide. Of these, urea and thiO- urea are preferred. By the incorporation of these carbamic acid derivatives in the present composition, the amount of the more expensive tetrakis-(alpha-hydroxyorgano) phosphonium halide compound can be reduced, over that required when compounds of this type are not present. Inasmuch as urea and thiourea are the preferred cerbamic acid derivatives for use in the present composition, specific reference to these materials will be made hereinafter.

The water-soluble tertiary amines which are suitable for use in the composition of the present invention are desirably water-soluble tertiary lower alkyl amines. Typical of those which may be used are triethylamine, tributylamine, trihexylamine, triethanolamine, triisopropanolamine, tripentanolamine and the like. Of these, triethanolamine is preferred and primary reference will be made hereinafter to this material.

The halogenated parafiins of the subject composition are halogenated aliphatic materials containing fromabout 16 to about 40 carbon atoms, in a straight or branched chain and containing from about 20 to about 80 percent of chemically combined halogen. Preferably, the halogenated paraffin is a chlorinated aliphatic material containing about 18 to 36 carbon atoms, in a straight or branched chain, and containing about to of chemically combined chlorine in a molecule thereof. Desirably, the chlorinated paratfin is dissolved in a suitable solvent, such as tolylene, kerosene, xylene, naphthalene, trichloroethylene, perchloroethylene, methylene chloride, petroleum soltvent, and the like, and an oil soluble emulsifier added thereto. This solvent may be incorporated into the present composition as such, or may be formed into a water emulsion by combining it with water, which emulsion is then added to the composition. Suitable dispersing or emulsifying agents which may be used are the non-ionic emulsifying and dispersing agents, such as the alkylated aryl polyether alcohols, and the like.

The polyvinyl halide composition is a resin containing at least 50% of the polyvinyl halide, such as polyvinyl chloride and polyvinyl bromide. Of these, polyvinyl chloride resins are preferred. If desired, these resins may be copolymers of vinyl chloride with other monomers, such as vinyl acetate, vinylidene chloride, the acrylates, and the like. Where copolymers are used, as has been indicated hereinabove, it is desirable that the resin material contain at least 50% of the polyvinyl chloride, and preferably at least 70 to of the polyvinyl chloride. The polyvinyl chloride composition may be added to the impregnating solution of the present invention as such, or it may be combined with the chlorinated paraffin material, preferably in the chlorinated parafiin emulsion.

As has been indicated hereinabove, the polyvinyl chlor'de composition is present in an amount not in excess of about 25% by weight of the chlorinated paraffin. The minimum amount of the polyvinyl chloride composition which may be used in that amount which will impart the desired durability to the composition without adversely affecting the soft hand of the treated cellulosic textile fabric. In some instances, amounts as low as 1% by weight of the chlorinated parafiin may be used to attain these results. Generally, however, it is desirable to use the polyvinyl chloride composition in an amount of at least 5% by weight of the chlorinated parafiin, with amounts within the range of about 5 to about 15% by weight of the chlorinated parafiin being preferred.

In addition to the above components, antimony oxide may also be included in the impregnating composition of the present invention. Where it is used, amounts within the range of about 3 to about 15% by weight of the aqueous impregnating solution are typical. Although any commercially available antimony oxide may be used in the composition, it has generally been found to be desirable to use a pigment grade of antimony oxide.

A preferred aqueous impregnating solution for use in the present invention is one having the following components in the amounts indicated:

Components: Percent by weight Tetrakis(hydroxymethyl phosphonium chloride 9.514.5 Trimethylolmelamine 5.2-8.0 Triethanolamine 3.3-5.1 Urea 3.3-5.1 Chlorinated paraffin containing an average of 24 carbon atoms and 50% by weight of chemically combined chlorine 9.0-13.5 Polyvinyl chloride 1.0-l.6 Antimony oxide 6.9-10.5 Water Balance Any cellulosic material such as cotton, rayon, ramie, jute, paper, cardboard, and the like, may be treated with the compositions of the present invention, such as those which have been set forth hereinabove. These compositions are, however, particularly effective when applied to cellulosic textiles in view of the improved durability to washing and softness of the textile hand which is obtained when using these compositions.

In preparing the aqueous impregnating composition of the present invention, the various components are admixed with sutficient water to provide an aqueous resin dispersion or emulsion containing between about 30 and about 60 percent by weight of total solids. Preferably, the resin dispersion contains between about 40 and 50% by weight total solids. The term total solids as used throughout the specification and claims, is intended to include both the solids that are dissolved in the aqueous component as well as those solids which are colloidally dispersed, or otherwise dispersed, in the aqueous dispersion or emulsion. The term dispersion," as used throughout the specification and claims, is intended to include the dispersions and/or emulsion that results from admixing the above defined non-aqueous components with the water, generally in the proportions as has been set forth hereinabove. It will be appreciated, however, that variations from these proportions may be made so long as the concentrations of total solids in the resulting aqueous dispersion is sufficient to provide an adequate resin add-on in the cellulosic material being treated.

In formulating this aqueous dispersion, agitation of the solution may be desirable in order to insure that the nonaqueous components will be substantially completely dissolved of dispersed in the aqueous portion of the solution. After the impregnating bath has been formed, it is preferably maintained at a temperature below about 30 degrees centigrade, in order to obtain maximum stability and useful bath life. Typial operating temperatures for the impregrating bath are about 18 to 30 degrees centrigrade. It will be appreciated, that both higher and lower temperatures may be used, although in some instances the use of temperatures substantially in excess of about 30 degrees centigrade may result in a reduction of the time of useful bath life. In this regard, it is to be noted that during periods of high ambient temperature, it may be desirable to use ice to cool the impregnating solution. In such instances, it has been found that replacement of about to about by weight of the water in the impregnating bath with ice will generally be sufficient to maintain the bath temperature within the desired range, without adversely affecting the concentration of the impregnating comnosition.

After the polymerizable impregnating solution has been prepared, it may be applied to the cellulosic textile materials to be treated in any convenient manner, such as by padding, spraying, roller applications or other impregnating techniques known to those in the art. Generally, the manner of applying the impregnating solution to ,the textile material will depend upon the physical form of the textile being treated. Where the textile material is in the form of yard goods, it has been found to be desirable to formulate the impregnating solution in a padding box and to immerse the textile material in the solution. Thereafter, the tetile material is passed through a pad, or a squeeze roll, or other suitable means for removing the solution in excess of that necessary to saturate the cellulosic material.

It is to be noted that an important factor in treating the cellulosic material yith the compositions of the present invention is the amount of resin add-on in the cellulosic materials which have been treated. In this regard, it is important that the cellulosic material is given a resin add-on which provides both satisfactory flame retardancy, and durability to washing, without adversely affecting the hand of the material. Accordingly, the minimum amount of resin add-on is at least that amount which will render the cellulosic material flame retardant, i.e., a flameretardant amount. Generally, it has been found that resin add-ons within the range of about 10 to about by weight of the cellulosic material treated are satisfactory, with resin add-ons of within the range of about 14 to about 30% by weight of the cellulosic material treated being preferred. It is to be a-ppreciaed, however, that resin add-ons which are either greater or less than these amounts may be used satisfactorily in some instances, depending upon the type and weight of the cellulosic material being treated.

For the most part, the resin add-on obtained in the treated cellulosic material is dependent upon the amount of wet pick-up of the polymerizable impregnating solution during the impregnation step. Accordingly, it is apparent that the control of the amount of wet pickup during the impregnating step is an important factor in carrying out the process of the present invention. Generally, it has been found that wet pick-ups in the range of about 65 to about 100% by weight of the material being treated will give a finished, flame-retardant product having the desired resin add-on. As with the resin add-on amounts, however, it is to be appreciated that wet pickup amounts which are both greater than and less than these preferred amounts may be used to give satisfactory results in some instances, depending upon the type and weight of the fabric which is being treated.

Once the cellulosic textile materials have been im pregnated with the polymerizable composition of the present invention and the desired wet pick-up has been obtained, drying and curing of the resin impregnated in the cellulosic material is effected. Various suitable techniques may be utilized to effect drying and curing of the impregnated cellulosic material. For example, the impregnated material may be dried in a conventional forced hot air oven at a temperature between about and about degrees centigrade for /2 to 15 minutes. Curing of the cellulosic material may be carried out in the same apparatus by heating at a temperature from about 120 to degrees centigrade for about 1 to 15 minutes. It will be appreciated, however, that any temperature and time conditions under which substantially all of the free water is removed from the cellulosic material and the resin is cured may be employed. For example, the impregnated cellulosic textile may be stored under atmospheric conditions over night to effect drying of the cloth and curing of the resin or the dry, resin coated textile may be cured in an infrared oven at a temperature between about 260 and 370 degrees centigrade for a period of about 5 to 12 seconds. I

Following the drying and curing of the resin impregnated cellulosic material, the material is preferably scoured or washed to remove any unpoly'merized materials and the like. For this operation, an'conventional scouring process, such as rope scouring, continuous openwidth scouring, jig scouring, and the like may be used. Typical of the scouring solutions which may be used are aqueous soap solutions containing small amounts of sodium carbonate and/0r sodium perborate. After scouring, the treated cellulosic material may then be dried, using the drying techniques as have been indicated hereinabove.

The thustreated resin impregnated cellulosic materials are found to be durably flame retardant, even after repeated washings and ironings. The durability of this flame retardancy is such that it lasts for the whole life of the fabric. In addition to this durability, it is found that the hand of the fabric is excellent, and that the fabric is both soft and flexible. The resin material with which the cellulosic textile fabric is impregnated is a reaction product of the components of the impregnating solution which contains those components in the amounts indicated:

Percent by weight of the resin Components: forming ingredients Tetrakis(alpha hyrdoxyorgano)phosphonium compound 10to 40 Water soluble cyclic nitrogen-containing compound 6 to 30 Water-soluble tertiary amine 4to 20 Carbamic acid derivative 4t0 2O Halogenated paraffin 10 to 35 Polyvinyl halide composition 1 to9 Additionally, where it is used, the resin composition will also cointain antimony oxide in an amount within the range of 8 to 35 percent by weght of the resin forming ingredient.

In order that those skilled in the art may better understand the present invention and the manner in which it may be practiced, the following examples are given. In these examples, unless otherwise indicated, the temperatures are in degrees centigrade and the amounts are in percent by weight. Additionally, the flame retardancies reported were determined in accordance with the procedure of the American Association of Textile Chemists and Colorists, Test AATCC Base 34-1952. Tensile strengths are determined in accordance with the procedure of Federal Specification CCCT-l9l6, 5100. Additionally, the stiffness of the treated fabric was determined using a Gurley stiffness tester.

7 EXAMPLE 1 The following solutions were prepared by admixing together the components in the amounts indicated:

A series of aqueous impregnating dispersion were then prepared using the above solutions in the amounts indicated.

Parts by Weight Components A B C D E F G Solution 290 290 290 200 290 290 290 Solution B 48.0 51.0 54.5 57.5 61.0 64.0

Polyvinyl chloride (aqueous dispersion containing 50% resin 64.0 16.0 13.0 9. 6.5 3.0 0 solids) Antimony oxide 26 26 26 26 2G 26 26 Percent by Weight Polyvinyl chloride based on chlorinated paraffin 100 25 20 10 5 0 A sample of an 8-ounce cotton duck was impregnated with each of the above impregnating solutions, one sample in each solution, by immersing the cloth in the impregnating solution and thereafter removing the excess solution by passing the fabric between squeeze rolls to obtain a wet pickup on the fabric of from 70 to 75% by weight. The fabric samples were then dried for 2.5 minutes at 120 degrees centigrade and then were cured for two minutes at about 165 degrees centigrade. The dried fabric was then washed with an aqueous soap solution containing 0.2% by weight of sodium carbonate and about 0.2% by weight sodium perborate to remove any unpolymerized materials from the fabric. The fabric samples were then redried and the tensile strength, stiffness and char length were then determined, using the procedures as have been indicated hereinabove. The results obtained were as follows:

Parts by Weight Components A l3 0 D E I" G Untreated Control ResinAdd-011(percent). .31 1f! 18 17 17 14 'lcnsile, till (in lbs. per

inch).. 1 118 05 98 108 104 06 04 112 Gurley stiffness warp (milligrams) 160 155 131 138 1'25 120 104 94 Char length (inches) (after wash)". 3,0 3.5 3. Atter5boilcycles 3.3 3.6 3.1

1 Burns after 2 boil cycles. 1 "Burns.

Similarly, when the impregnating composition contains no polyvinyl chloride, but only the chlorinated paraflin, although the hand of the fabric is greatly improved, as shown by the lower stiffness rating there is an appreciable decrease in the durability of the flame retarding treatment, as evidenced by the fact that the treated fabric burns after only 10 washings. In contrast, however, where the composition contains no more than about 25% of the polyvinyl chloride, based on the chlorinated paraffin, and preferably from about 5 to about 15%, durable flame retardancy is obtained, while retaining a soft and improved hand.

EXAMPLE 2 An emulsion was prepared by admixing the following components in the amounts indicated, the components being added in the order shown:

Components: Parts by weight Chlorinated parafiin containing an average of 26 carbon atoms and 46% of chemically combined chlorine per molecule 165.0 Alkylated aryl polyether alcohol 10.0 Xylene 49.5

Polyvinyl chloride resin (aqueous dispersion containing 55% resin solids) Water Using this emulsion, the following impregnating pad bath was prepared by admixing the components in the amounts shown, the components being added in the order shown:

Components: Parts by weight Water 406 Trimethylol melamine 62 Triethanol amine 40 Tetrakis(hydroxymethyl)phosphonium chloride (aqueous dispersion containing by weight of solids) 137 Urea 40 Alkylated aryl polyether alcohol 6 Emulsion, as prepared above 228 Antimony oxide 81 Char length initially 3.5 After 5 boil cycles 3.1 After 9 boil cycles 4.1 After 13 boil cycles 4.3 After 17 boil cycles 4.3

The boil cycles to which the treated fabric is subjected, as referred to above, consist of boiling the sample for one hour in an aqueous solution containing about 0.2% soap and about 0.2% sodium carbonate. Thereafter, the fabric is rinsed in clear water. This constitutes one boil cycle.

When the procedure of the above example is repeated using other carbamic acid derivatives such as thiourea, biuret, ethylene urea, dicyandiamide; other tertiary alkyl amines, such as triethyl amine, tributyl amine, tripropanol amine, and the like; other vinyl halide compositions, such as co-coplymers of vinyl chloride and vinylidene chloride, co-polymers of vinyl chloride and vinyl acetate, both of which contain at least 50% vinyl chloride, and the like; and other water-soluble cyclic nitrogen contain ing compounds, such as dimethylolmelamine, dimethylol triazone, dimethylolpropylene urea, and the like, similar results are obtained.

While there have been described various embodiments of the invention, the compositions and methods described are not intended to be understood as limitnig the scope of the invention, as it is realized that changes therewithin are possible and it is further intended that each element recited in any of the following claims is to be understood as referring to all equivalent elements for accomplishing substantially the same results in substantially the same or equivalent manner, it being intended to cover the invention broadly in whatever form its principle may be utilized.

What is claimed is:

1. A composition suitable, when dispersed in a solvent, for treating a cellulosic material to render it flame retardant which composition comprises from about 6-20% by weight of a tetrakis(alpha-hydroxyorgano)phosphonium halide, a water-soluble cyclic-nitrogen containing compound, a water-soluble tertiary amine, a carbamic acid derivative, from about 214% by Weight of a halogenated paraffin, and a polyvinyl halide composition, in an amount of about 1 to 25% by weight of the halogenated paraffin.

2. A composition for treating a cellulosic material to render it flame retardant, which composition comprises a water-soluble cyclic nitrogen containing compound, a Water-soluble tertiary amine, a carbamic acid derivative, from about 214% by weight of a halogenated parafiin, a polyvinyl halide composition in an amount of about 1 to 25% by weight of the halogenated paraflin, water, and from about 6-20% by weight of a tetrakis(alphahydroxyorgano)phosphonium halide having the formula:

wherein R is selected from the group consisting of hydrogen, lower alkyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkyl radicals having between about 1 and about 6 carbon atoms, lower alkenyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkenyl radicals having between about 1 and about 6 carbon atoms, aryl radicals having between about and about 10 carbon atoms, halogenated aryl radicals having between about 5 and about 10 carbon atoms, cycloalkyl radicals having between about 3 and about 6 carbon atoms, and halogenated cycloalkyl radicals having between 3 and about 6 carbon atoms, and wherein X is halogen.

3. A composition for treating a cellulosic material to render it flame retardant, which composition comprises from about 3 to 12% by weight of a water-soluble cyclic nitrogen containing compound, from about 1 to 4% by weight-of a water-soluble tertiary amine, from about 3 to 12% by weight of a carbamic acid derivative, from about 2 to 14% by weight of a halogenated paratfin, from about 6 to by weight of a tetrakis(alpha-hydroxyorgano) phosphonium halide, a polyvinyl halide composition in an amount of from about 5 to 15% by weight of the halogenated paraffin, the remainder of the composition being water and the percents being by Weight of the composition, and wherein the phosphonium halide has the formula:

wherein R is selected from the group consisting of hydrogen, lower alkyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkyl radicals having between about 1 and about 6 carbon atoms, lower alkenyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkenyl radicals having between about 1 and about 6 carbon atoms, aryl radicals having between about 5 and about 10 carbon atoms, halogenated aryl radicals having between about 5 and about 10 carbon atoms, cycloalkyl radicals having between about 3 and about 6 carbon atoms, and halogenated cycloalkyl radicals having between about 3 and about 6 carbon atoms, and wherein X is halogen.

4. The composition as claimed in claim 3 wherein the phosphonium halide compound is tetrakis(hydroxymethyl) phosphonium chloride, the cyclic nitrogen-containing compound is trimethylolmelamine, the tertiary amine is triethanolamine, the carbamic acid derivative is urea, the vinyl halide is vinyl chloride and the halogenated paraffin is a chlorinated paraffin.

5. The composition as claimed in claim 4 wherein there is also present antimony oxide in an amount within the range of about 3 to about 15 percent by weight of the composition.

6. A method for treating a cellulosic textile material to render it flame retardant which comprises impregnating the cellulosic textile material with a polymerizable composition from about 6-20% by weight of comprising a tetrakis(alpha hydroxyorgano)phosphonium halide, a water-soluble cyclic nitrogen-containing compound, a water-soluble tertiary amine, a carbamic acid derivative from about 2-14% .by weight of a halogenated parafl'ln, a polyvinyl halide composition in an amount of about 1 to 25 percent by weight of the halogenated paraffin, and water, and, thereafter, curing the thus-impregnated cellulosic textile material.

7. A method for treating a cellulosic textile material to render it flame retardant which comprises impregnating the cellulosic material with an aqueous solution comprising a water-soluble cyclic nitrogen-containing compound, a water-soluble tertiary amine, a carbamic acid derivative, from about 2-14% by weight of a halogenated parafiin, a polyvinyl halide composition in an amount of about 1 to 25 percent by weight of the halogenated paraflin, water, and from about 620% by weight of a tetrakis(alphahydroxyorgano) phosphonium halide compound having the formula:

wherein R is selected from the group consisting of hydrogen, lower alkyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkyl radicals having between about 1 and about 6 carbon atoms, lower alkenyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkenyl radicals having between about 1 and about 6 carbon atoms, aryl radicals having between about 5 and about 10 carbon atoms, halogenated aryl radicals having between about 5 and about 10 carbon atoms, cycloalkyl radicals having between about 3 and about 6 carbon atoms, and wherein X is halogen, and, thereafter, curing the thus-impregnated cellulosic material.

8. A method for treating a cellulosic textile material to render it flame retardant which comprises impregnating the cellulosic material with an aqueous solution comprising from about 3 to 12% by weight of a water-soluble cyclic nitrogen containing compound, from about 1 to 4% by weight of a water-soluble tertiary amine, from about 3 to 12% by weight of a carbamic acid derivative, from about 2 to 14% by weight of a halogenated parafiin, from about 6 to 20% by weight of a tetrakis(alpha-hydroxyorgano)phosphonium halide, a polyvinyl halide composition in an amount. of from about 5 to 15% by weight of the halogenated paraffin, the remainder of the composition being water and the percents being by weight of the aqueous composition, wherein the phosphonium halide has the formula:

wherein R is selected from the group consisting of hydrogen, lower alkyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkyl radicals having between about 1 and about 6 carbon atoms, lower alkenyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkenyl radicals having between about 1 and about 6 carbon atoms, aryl radicals having between about 5 and about 10 carbon atoms, halogenated aryl radicals having between about 5 and about 10 carbon atoms, cycloalkyl radicals having between about 3 and about 6 carbon atoms, and halogenated cycloalkyl radicals having between about 3 and about 6 carbon atoms, and wherein X is halogen, and, thereafter, curing the thus-impregnated cellulosic material.

9. The method as claimed in claim 8 wherein the phosphonium halide compound is tetrakis(hydroxymethyl) phosphonium chloride, the cyclic nitrogen-containing compound is trimethylolmelamine, the tertiary amine is triethanolamine, the carbamic acid derivative is urea, the polyvinyl halide is polyvinyl chloride and the halogenated paraflin is a chlorinated parafiin.

10. The method as claimed in claim 9 wherein there is also present in the aqueous impregnating composition antimony oxide in an amount within the range of about 3 to about 15 percent by weight of the aqueous composition.

11. A flame retardant cellulosic material comprised of a cellulosic material impregnated with a resinous material, said resinous material being the reaction product formed from resin forming ingredients comprised of from about 10-40% by weight of a tetrakis(alpha-hydroxyorgano)phosphonium halide, a water-soluble cyclic nitrogen-containing compound, a water-soluble tertiary amine, a carbamic acid derivative, from about 10-35% by weight of a hologenated paraflin, and a polyvinyl halide composition in an amount of about 1 to 25 percent by weight of the halogenated paraflin,

12. A flame retardant cellulosic material comprised of a cellulosic material impregnated with a resinous material, said resinous material being the reaction product formed from resin forming ingredients comprised of a water-soluble cyclic nitrogen-containing compound, a water-soluble tertiary amine, a carbamic acid derivative, from about 1035% by weight of a halogenated parafiin, a polyvinyl halide composition in an amount of about 1 to 25 percent by weight of the halogenated paraflin, and from about 10-40% by weight of a tetrakis(alpha-hydroxyorgano)phosphonium halide having the formula:

III R-(Q) PK II 4 wherein R is selected from the group consisting of hydro gen, lower alkyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkyl radicals having between about 1 and about 6 carbon atoms, lower alkenyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkenyl radicals having between about 1 and 6 carbon atoms, aryl radicals having between about and about carbon atoms, halogenated aryl radicals having between about 5 and about 10 carbon atoms, cycloalkyl radicals having between about 3 and about 6 carbon atoms, and halogenated cycloalkyl having between about 3 and about 6 carbon atoms, and wherein X is halogen.

13. A flame-retardant cellulosic material comprised of a cellulosic material impregnated with a resinous material, said resinous material being the reaction product formed from resin forming ingredients comprised of from about 6 to 30% by weight of a water-soluble cyclic nitrogen-containing compound, from about 4 to 20% by weight of a water-soluble tertiary amine, from 4 to 20% by weight of a carbamic acid derivative, from about 10 to 35% by weight of a halogenated paratfin, from about 10 to 40% by weight of a tetrakis(alpha'hydroxyorgano)phosphonium halide, and a polyvinyl halide composition in an amount from about 5 to 15% by weight of the halogenated paraffin, all of the percents being percent by weight of the resin forming ingredients in the composition, and wherein the phosphonium halide has the formula:

wherein R is selected from the group consisting of hydrogen, lower alkyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkyl radicals having between about 1 and about 6 carbon atoms, lower alkenyl radicals having between about 1 and about 6 carbon atoms, halogenated lower alkenyl radicals having between about 1 and about 6 carbon atoms, aryl radicals having between about 5 and about 10 carbon atoms, halogenated aryl radicals having between about 5 and about 10 carbon atoms, cycloalkyl radicals having between about 3 and about 6 carbon atoms, and halogenated cycloalkyl radicals having between about 3 and about 6 carbon atoms, and wherein X is halogen.

14. The flame retardant cellulosic material as claimed in claim 13 wherein the phosphonium halide compound is tetrakis (hydroxymethyl) phosphonium chloride, the cyclic nitrogen-containing compound is trimethylolmelamine, the tertiary amine is triethanolamine, the carbamic acid derivative is urea, the polyvinyl halide is polyvinyl chloride and the halogenated paraflin is a chlorinated paraflin.

15. The flame retardant cellulosic material as claimed in claim 14 wherein the resinous impregnating material also contains antimony oxide in an amount within the range of about 8 to about 35 percent by weight of the resin forming ingredients.

References Cited UNITED STATES PATENTS 2,378,715 6/1945 Leatherman 26028.5 X 2,421,409 6/1947 Brookman et a1. 26028.5 X 2,461,538 2/ 1949 Fischer. 2,775,994 l/1957 Rowe W 10615 X 3,054,698 9/1962 Wagner 117-136 OTHER REFERENCES Buttrey, D. N., Plasticizers (1957), Cleaver-Hume Press Ltd., London, pp. 146 and 147.

WILLIAM D. MARTIN, Primary Examiner.

H. I. GWINNELL, Assistant Examiner.

US. Cl. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,428,480 February 18, 1969 George M. Wagner et al.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 18, solube" should read soluble line 35, "wich" should read which Column 3, line 27, "triethyl" vshould read trimethyl line 67, "solvent may" should read solvent solution may Column 4, line 17, "in" should read is Column 5, line 38, "tetile should read textile line 43, "yith" should read: with line 57, "appreciaed" should read appreciated Column 6, line 60, "cointain" should read contain line 61, "weght" should read weight Column 8, line 70, "co-coplymers" shouldread co-polymers Column 9, line 5 limitnig" should read limiting Column 10, line 23, "from about 620% by weight of comprising" should read comprising" from about 6-20% by weight of Column 11, line 42, "hologenated" should read halogenated Column 12, line 1, "cycloalkyl" should read cycloalkyl radicals Signed and sealed this 31st day of March 1970.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. I WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents 

